CaptBeach

Truck (78 W200) has tank behind rear seat...I have plenty of room under the Step Side Bed and inside the frame rails to add tankage...

My plan is to eventually to the Cummins deisel swap once I've sorted everything else out..gotten it semi restored and daily drivable...

What would you do? What tanks would you find to install? I might keep the interior tank as I think its 29 gallons(?) and add more under the truck...

TVLynn

For something like that I would check with J C Whitney Co
Could also go to Summitracing.com for a fuel cell

CaptBeach

had not thought of that...Fuel cells...hmmmm

RacerHog

Use a 1977 Dodge D150 Step side fuel tank. it mounts on the inside of the drivers side frame rail. But you will have to move your exhaust to the right hand side of the truck.
I also use to have a custom rear fuel tank mounted back at the rear of the truck were the spare tire use to mount, it was 30 gal. and I installed a transfer pump to move the fuel to the front tank. To fill the rear tank, the filler neck was mounted between the rear bumper and the bed.

CaptBeach

Moving the exhaust is not a problem...have not welded all the joins yet...thats a good idea too...

RacerHog

http://ramchargercentral.com/vehicle...estion-advice/


You get the Drift...

ZombiePopper

????
Just buy the orig fuel tank/hardware that came equipped on a lot those trucks.
It was positioned under the bed, drivers side.

In my 73 power wagon my truck originally was a duel tank truck (1 behind seat and 1 under the bed, drivers side.)
I pulled the tank out of the cab and just ran off the tank that was In between the frame rails under the bed no prob.
Then I swapped my regular long bed to a long stepside bed and I didn't have any issues using the same fuel tank set-up (IN FACT, I didn't even touch my tank set-up, I just swapped my beds.) there's no difference between the regular bed and stepside bed fuel tanks (besides filler necks) BUT I did have to swap to the stepside fuel filler neck (obviously), but that's it, again no prob.
I was running headers and I just ran my exhaust straight down the center of my truck (on either side of the driveshaft just below it) and had them dump before the rear wheels, no prob. (I was debating about going to stacks straight up out of the bed behind the cab lol)
At one point, I tried to upgrade to a bigger fuel tank and that's where things get REAL interesting, REAL quick.
A tank that's to long is going to smack the T-case, a tank to wide is going to get into the driveshaft, so you need the EXACT tank/hardware that came equipped on the W series trucks, it'll bolt right in Like it was made for it...because it was.
I do recommend using some folded up inner-tube on the tank straps and do NOT over torque the tank straps.
Do NOT use the ramcharger fuel tanks, they will NOT fit, ask me how I know lol.
Also, I don't THINK that ALL D series truck's tanks will fit, they were a 2wd and the W series is a 4wd and hence, had a T-case that the D series didn't. So I BELIEVE, the D series tank was longer (?) But I'll let someone verify that, your best bet is to pull the entire tank set-up out of a W series.

DodgeAddict

I use RamCharger tanks & crossmembers

The holes are already in the frame
Here's pics of all of it
In & out of the frame

ZombiePopper

I don't agree with the RC tanks fitting.
when I had my 73 PW, the orig fuel tank had cracks in it where a previous owner over tightened the tank straps,
I tried to patch the tank but of course that didn't work,
everyone told me "the RC tank would work"
so I found a guy in TX selling RC parts and bought a gas tank from him,
guess what?
The RC Tank would NOT fit in my PW, it hit the t-case and tank straps wouldn't go around the tank, it didn't fit.
With that said, I'm not sure what year of RC the tank came off of but its plastic so probably, late 70's-80's,
Not sure if you've ever done this swap(?) but he's better off just buying the tank set-up off a W series truck and calling it done.

DodgeAddict

You weren't using the RC tank & your 73 PW didn't have an under cab tank from the factory unless it had dual tanks & then it would have a in cab tank as well & only one filler neck in the cab for both tanks

I'm not sure if you've ever done this swap but Dodge did & so have I many times

The RC tank has been used as the second tank in a dual tank option starting in 1975 & ending in 1985 or 1986

If you look at the pic of the frame that's the same tank mounted as in the other pic

ZombiePopper

As I stated in my first post, my PW WAS a dual tank truck.
Ill stand by my comment that that he's better off just buying a tank set-up off a W series.

DodgeAddict

There's no difference in a D or W on the tank

John Angel Shoemaker

Where to get a gas tank for a 78 w150

Iowan

They are getting hard to find and when you do it's still a 40 year old tank.
good luck

George Az

I had a cracked fuel tank on my 79 D 150. I searched all kinds of junk yards and the internet. I wound up with an RCI fuel cell in the bed of the truck. Seems like stock these plastic tanks don't last 40 years. I have found some other tanks at the junk yard which would need fabrication to fit, far more so than the fuel cell. I am still looking for a solution. and in the future would love to take the time, pull my bed and fab up something to fit in the original location using the filler neck and stock gas cap. It is easy enough to do, it just takes time and measurements. In the mean time, if you are willing to give up the spare tire area, there are fuel cells/tank which fit between the bed rails and to fill go through the bed. They use a small flush fitting cap like on a boat. It is really a clean install.

On the plus side, I have had zero issues with my RCI fuel cell and it looks and works very well. I lost a small amount of bed space for approximately 20 gallons. For a while, I had a truck tool box which I cut a hole in the bottom of so my cell was hidden and somewhat protected from sun and fingers. It limited what I could put in the box, but it was functional and meant I had to open the tool box every time I wanted to fill up. But I never had gas smell or problems because I properly vented it. I used all braided stainless lines too and through wall fittings. I ordered everything from Summit. I hit the junk yards every few weeks hoping, but many of the fuel tanks have all kinds of vents and lines which will have to be plugged. I fit the proper fuel gauge to the RCI sending unit and while it bobs the gauge when fuel sloshes around, that is when it is about 1/2 tank or less. Many tanks have the Chevy sending units, they are cheaper but it does cause you a small ohm problem, so I replaced the gauge. I might give up my spare tire area and do the under the bed thing, it would give me my bed back, but then I am left with mounting a spare in the bed, so it is a trade off.

If you have or want to use diesel fuel there is a really nice fuel/tool box combo which holds 50 gallons or some such amount, it isn't cheap but it looks and works awesome. I wouldn't feel safe putting gasoline in it though.
Good luck.